Selegiline (Eldepryl, Zelapar)
MAOI • Last reviewed 2025-09-27
General information
Oral selegiline is a selective MAO-B inhibitor used primarily for Parkinson disease but at higher doses provides antidepressant benefit when combined with dietary restrictions.
Metabolism produces amphetamine and methamphetamine derivatives that can cause insomnia, agitation, and increased blood pressure.
Patients require counseling on tyramine restrictions when using doses ≥10 mg/day or when combined with other serotonergic agents.
Therapeutic effects persist 1–2 weeks due to irreversible enzyme inhibition; washouts are required when switching therapies.
Dosing & administration
Depression (off-label): 5 mg twice daily tablets or 1.25–2.5 mg ODT once daily.
Avoid evening dosing to minimize insomnia; allow 14-day washout before/after serotonergic or adrenergic drugs.
Dose adjustments not required for mild hepatic/renal impairment but monitor closely.
Mechanism of action
Selectively inhibits MAO-B at low doses, increasing dopamine; higher doses inhibit MAO-A, augmenting serotonin and norepinephrine.
Metabolism & pharmacokinetics
Peak concentrations within 1 hour; half-life ~10 h though enzyme inhibition lasts longer. Metabolized via CYP2B6/CYP2C19/CYP3A4 to active metabolites excreted renally.
Drug interactions
Contraindicated with SSRIs, SNRIs, TCAs, bupropion, meperidine, tramadol, and dextromethorphan.
Sympathomimetics and stimulants increase hypertensive crisis risk.
Avoid tyramine-rich foods once doses reach 10 mg/day.
Monitoring & safety checks
Blood pressure and signs of hypertensive crisis
Sleep pattern, agitation
Medication list review for serotonergic agents
Discontinuation guidance
Taper over 1–2 weeks; maintain tyramine restrictions for 14 days after discontinuation.
References
- Selegiline Oral Prescribing Information — DailyMed
- Clinical management of oral MAOIs — Journal of Clinical Psychopharmacology (2022)
- CANMAT recommendations for oral MAOIs — Canadian Journal of Psychiatry (2024)
Educational use only — verify details in current prescribing information and authoritative clinical guidelines before making prescribing decisions.